Flashlight



March 29, 1960 w. im. LENNAN FLASHLIGHT Filed March l1, 1957 UnitedStMCSPatenf o FLASHLIGHT William M. Lennan, Los Angeles, Calif.Application March 11, 1957,*Serial No. 645,313

9 Claims. (Cl. 24U-11.3)

The present invention relates generally to flashlights and moreparticularly to an improved flashlight that is adapted for safe useunder certain hazardous conditions.

Under many circumstances flashlights must be used in potentiallydangerous situations. For example, they may be employed to inspect theinteriors of tanks that contain combustible or explosive atmospheres. Ifthe light is inadvertently dropped so that its lens or bulb is broken,fire or explosionmay result due to arcing across the bulb filaments.Similarly as a result of dropping the flashlight a spark may be struckby its impact on the tank. Such a spark may also be suflicient to ignitean explosive atmosphere. Recognizing this hazard, underwriters requirethat flashlights used in such situations be adapted to avoid anypossibility of arcing or sparking resulting from dro ping the light orother such accident.

An object of my invention is to provide a flashlight that has means toautomatically electrically disconnect its bulb from its batteries in theevent of breakage of its lens or bulb. By these means any possibility ofthe bulb filaments arcing or continuing to burn in an explosiveatmosphere is eliminated. y Another object'of my invention isto providea flashlight of this character that is provided with a resilient outercover that will absorb the impact of any fall of the light and thereforewill not cause a spark when struck against a metal surface.Additionally, this outer cover is adapted to support the lens ofthelight in such a way as to define a fluid sealed housing that preventsany entrance of a potentially explosive atmosphere into Contact with thehot light bulb.

A still further object of my invention is to provide a. novel form ofbulb mountingv means for a-flashlight that is of simplified, inexpensiveconstruction. This mounting means is adapted to receive bulbs withthreaded or Unthreaded bases and in either case will automatically ejectthe bulb in the event of fracture of the flashlight lens or bulb. y'

- The invention also has for an object the provision of a safetyflashlight of this character that is adaptedfto carry` a spare bulb in aprotected position wherein it will not be broken even if the flashlightis dropped.

These and other objects and advantages of the invention will be apparentfrom the following description of a presentlypreferred embodimentthereof and from the drawing annexedhereto in which: v Figure l is alongitudinal section through a flashlight embodying my invention, andshowing the normal position of ailashlight bulb in the bulb mountingmeans;

FigureZ isa partial longitudinal section-on an enlarged scale similar toFigure 1 showing the switch closed and aV brokenb-ulb ejectedfrom-electrical, connection with the f batteries of the flashlight; and

l,Figure 3 is a transverse sectional View on. an enlarged scale takenalong the lineA3-3 of Figure l, andshowing details of the bulb mountingmeans and flashlight switch. j Referring now to ,thedrawing for `thegeneral arrange- Patented Mar. 29,`

'nat

nated generally by the reference numeral 10. As is shown in Figure 1,the flashlight 10 includes tubular outer casing 11 which is made ofrubber, neoprene or other similar elastomer having a closed end and anopen end which carries a lens 12. The outer casing 11 and lens 12together define a fluid-sealed housing in which an inner shell 13 isremovably disposed that is adapted to support a plurality of replaceablebatteries 14 between a base spring 15 and bulb socket 16. A bulb 17 isseated in socket 16 by means of a lens spring 18 that normally maintainsbulb 17 in electrical connection with resiliently mounted contact meansdesignated generally at 19. The inner shell 13 also carries switch means20 operablefrom the outside of casing 11 by means of which the light maybe turned on and off.

a Specifically, the inner shell 13 is of substantially semicylindricalconfiguration and is preferably made of a metal such as steel. ventionas embodied in a three cell flashlight but it will be understood thatthe inner shell 13 can be adapted lto accommodate any number of cells.As is shown by the dotted outline in Figure l, the rear portion 21 or"theA shell 13 is of slightly greater than semi-cylindricalconfiguration, while the forward portion `22 of shell 13,isv slightlyless than semi-cylindrical in configuration. vThe Y forward portion 22thus defines a ready entrance for. the

" defined by the cup flange 27, the keeper 29 is pressedv ment 'of theinvention my improved flashlight is desig introduction of batteries 14into the shell 13 while the rear portion 21 is adapted to prevent anylateral displacement of batteries 14 from the shell 13.

The rear end of shell 13 is formed with an inwardly turned cup-likeflange 23. Seated on diametrically opposite portions of the flange 23 isa spare bulb holder 24 thatincludes a pair of resilient clips 25 betweenwhich the stem of a spare bulb 17a is frictionally held. The.' basespring 15 is compressed between the rear battery 14 and the holder 24and flange 23`to retain the holder in place as well as to electricallyconnect batteries 14 to case 13. Rigidly afxed to the front end of theshell 13 is a generally conically'shaped reflector cup 26 concentricallyaligned with the shell 13 with its reduced rear end formed with aradially inwardly turned flange 27. The opening defined by the flange 27is adapted to slidably receive acylindrical crown 28 which .is formed onthe forward end ofthe socket 16. The cup flange 27'is adapted to seat anannular socket keeper 29 made of a resiliently deformable material such.as Phosphor bronze formed with a plurality ,of radially inwardlyinclined fingers 3l) which normally define an aperture of less diameterthan the socket crown 28. After the crown 28 of socket 16 is placed inposition through the opening downwardlythereover and seated inplace onthe flange 27. This seating of keeper 29 results in deformation of thefingers 30 to the positions shown in Figures l and 2 wherein the fingers30 have yielded to permit insertion of crown 28 therethrough. Whenkeeper 29 is fullyseated on flange 27, socket i6 is rigidly held inplace between said keeper and the shoulder dened between crown 28 andthe base portion 31 of the socket 16. Any tendency towards displacementof socket 16 is resisted by the engagement of lingers 30 with the socketcrown 28.

ISocket 16 is especially adapted for use with a bulbI 137 of the typeshown in the drawings. However, aswill presently appear the socket canalso be used with the ordinary type of flashlight bulb which includes athreaded base. The bulb 17 shown in the drawings hasa smooth cylindricalbase 32 which constitutes one'of the terminals thereof. It will beobserved that the rear end of the bulb base 32 is slightly rolledinwardly asis indicated generally by the reference numeral 33. Bulb-"17alsol includes a rearwardly protruding centrally disposed ter@ In Figurel, l have shown my inagresse,

nrinal 34 which is insulated from cylindrical base 32. The terminals 32and 34 are electrically connected by a filament 35 which is encased in abulb envelope 36. The iirst terminal or base 32 of the bulb at itsjunction with the envelope 36 is formed with an outwardly extendingannular flange 37.

The socket 16 is formed with an axial bore 33 extending therethroughwhich is adapted to loosely receive" the bulb base 32 therein. Theforward end of socket 16 has a spot face designated at 39 formedconcentrically with bore 3SY which is adapted to seat the bulb flange37. As is shown in Figure l, the lens spring 18 is adapted to engage thebulb envelope 36 at one end thereof, the other end of spring 1S beingembedded in the lens 12 which is preferably made of a clear plasticmaterial, such as that commercially available under the. name LuciteThis arrangement serves to keep the bulb 17 firmly but removably seatedin the socket 16. The cup 26 rigidly mounts a concentrically alignedpoiished reflector 465 and as will be observed in Figure l when the bulb17 is seated in socket 16 by the aforedescribed means it is correctlydisposed relatively to reflector 4h.

A screw type ashlightfbulb can alsorbe used with the bulb mounting meansjust described. This type of bulb does not have any base flange forseating engagement' with the socket spot-face 39 but can nevertheless befirmly held in place between the opposed lens spring 1S and resilientcontact means 19, presently to be described.

Contactv means 1 includes a battery Contact spring 41 formed of asubstantially rectangular piece of a conductive material having a finger44 formed as a sidewardL continuation thereof. The spring 41 is fastenedto the reary face of socket 16 by means of rivets 45 or thel'ike (Fig. 3)V with the finger 44 folded forwardly thereover (Fig. 2) to be disposedin a channel 43 that 'extends radially outwardly from socket bore 38towards switch means 2.0. A rearwardly protruding dimple 46 on spring 41contacts the center terminal of the adjacent battery 14. Referring toFigure l, it will be seen that when bulb 17 is seated in socket 16 thatits center terminal 34 makes contact with the finger 44 of spring'41 andalso depresses said finger. The bulb 17 is thus electrically connectedto batteries v14 and at the same time is subject to the biasing actionof the depressed resilient finger 44.

The circuit through bulb 17 is completed by an ejector spring 42 ofgenerally L-shaped configuration such as can be seen in Figures l and 2.As is shown in Figure 3, the ejector 42 is slightly less in width thanthev socket channel 43 and is secured at its central portion to the oorof the channel by a rivet 75. The inner end 47 of the ejector isbifurcated as indicated in dotted outline in Figure 3 to provideclearancebetween the arms thereof through which the central terminal 34ofV bulb '17 can pass without contacting ejector 42. This spacingbetween the arms of ejector end 47 is slightly less than the diameter ofthe base 32 of bulb 17 so that said arms will engage the inwardly rolledrear end 33 of bulb base 32.

The reason for this arrangement will be apparent from an examination ofFigure l. It will be seen that the endl 33 of. the seated bulb 17 hasdepressed the bifurcated inner end 47 of ejector 42. Thus, both ejector42 andl battery Contactv spring 41 at all times urge bulb 17 outoisocket 16. So long as the bulb envelope 36 and lens I2 remain intact,bulb 17 will be held in seated position byv lens spring l which isstronger than the combined force of ejector 42 andv battery contactspring 41. When either. lens. 12 or bulb envelope 36 is broken. lensspring 18 no longer holds bulb `17 seated in socket 16 so thatthe bulbis then thrust out of the socket by` ejectorA 42 ajnd` batteryl Contactspring 41, as in Figure 2, to electricall'y, disconnect theV bulb frombatteries14.

Thelouter end 4S. of eiector spring 42 extends through an openingV v49formedA in. the wall of shellA 13. This outelrend 48 isrnormallydisposed in the position shown.

in Figure l wherein switch 2li is shown in open position.

When the switch 20 isk closed by` depression of itsforward end intocontact with outer end 48 the circuit is closed to seated bulb 17.

The switch means 2@ includes a switch frame 50 which may be secured tothe shell 13 in any desired manner. In its opposed side walls the frame50 has two pairs of oppositely disposed apertures 51 and 52 such as areindicated in dotted outline in Figures l and 2. Positioned in the frame5l) are a forwardly disposed lever 53 and a rearwardly disposed trigger54. The lever 53 has spaced apart downwardly extending side walls whichare formed with oppositely disposed outstruck' trunnions 55 adapted tobe positioned in the pair of apertures 51. The trigger 54, like lever53, also includes spaced side walls having trunnions 56 formed thereonadapted to be held in the frame apertures 52.

` In the open position of switch means 2t?, the forward endv of thetrigger 54 overiies the rear end of the lever 53 as is shown in Figurel. A ilat spring 57'is disposed in the switch frame 5) below lever 53and trigger 54, and includes upturned end portions one of which engagesthe forward portion of the lever 53 and the other of which engages therearward portion of the trigger 54 and retains the lever and triggerinopen position.

These switch means Ztl are substantially identicalto the switchdisclosed in my United StatesA Patent No. 2,176,084 and are fullydescribed therein. It will be apparent that when the forward end oflever 53 is depressed, it comes into contact with the outer end 48 ofthe ejector contact spring 4Z. As is clearly set forth in said patent,the switch means 251 may be selectively locked in closed position byfully depressing the forward end. of the lever 53 in order to snap therear end of lever 153 above the forward end of trigger 54. In order torelease the switchv from closed position, the trigger 54 is depressed toreturn the several parts to the position shown. inFigure l.

The outer casing 11 is preferably made of a flexible rubber materialorga. syntheticsuch as neoprene. Casing 11 is substantially cylindricaland is closed at oneend by and integral wall 5S. As is shown in Figure.l, the end wall 58 isspaeed. inwardly to provide a recess 59 adapted toreceive a carrying ring 60 which is carried by aboss 61. It will beobserved that ring 6% can be folded intro the recess 59 so that no partof it protrudes outwardly of the casing 11. With this construction eventhough the flash.- light 10 is dropped, if the ring has been placed inthisv secure position there will be no danger of. the metal ring cominginto contact with other metal in order to strike a spark.

At its front end the outer casing 11 isformed with an integral enlargedportion 62 which is adapted. to receive the switch means 20. Theenlarged portion 62 is formed with a forwardly disposed depression 63positioned oven the lever 53 and at its rear end is formed with adepression 64 positioned over the trigger 54. Thus, whenV the innershell 13 is placed inside the outer casing 11. the switch means 2l)v canbe actuated by pressure exerted'. on the depressions 63 and 64 which arerelatively thinwalled.

The forward end of the casing 11 is formed witha'n internal annulargroove 65 which is adapted to receive.v the beadedV periphery of lens12. Thus after batteries' 14 have been placed in theinner: shell 13 itis then slipped into the` casing 11. The bulb 17 is then placed inposi'tion in the socket 16 after which the open end ofthecasingfcan bedeformed to force the lens 12 into position inY At' the samev time theinwardlyJ rolled end. 33 ofthe bulb a) base 32 will depress theresilient bifurcated end 47 ofthe ejector contact spring 42. Bulb 17 isthus electrically connected to the batteries 14.

The operation of the invention is extremely simple. After the ashlighthas been assembled in the aforedescribed manner it may be turned on andoff merely by depressing the depressions 63 and 64, respectively.Assuming the flashlight to be 011, in the event that the envelope 36 ofbulb 17 should break, the bulb 17 is at once thrust outwardly of socket16 by the action of ejector 42 and battery contact spring 41. Bothterminals of the bulb 17 are thus taken out of contact with the contactsprings 41 and 42 in the manner shown in Figure 2, Accordingly, even ifthe filament 35 should remain intact it will no longer glow or if thefilament 35 is broken no arcing across protruding ends thereof will takeplacesince the bulb 17 is no longer electrically connected to thebatteries 14. The same result will follow if lens 12 is broken.

While there has been shown herein what is considered to be the preferredembodiment of the present invention, it Will be apparent that variousmodifications and changes may be made with respect to the foregoingdescription without departing from the spirit of the invention or thescope of the following claims. j Iclaim:

l. In a flashlight the combination of: a bulb socket made of insulatingmaterial; spring means extending between the lens of said ashlight andthe envelope of a bulb to seat said. bulb in said socket; a batterycontact spring mounted on said socket that yields to contact therewithof one terminal of said seated bulb and is engageable by one terminal ofa battery placed in said liashlight; an ejector contact spring mountedon said socket that yieldably engages the other `terminal of said bulb,

said'battery contact spring and ejector contact spring together servingto electrically connect said bulb to battery, n

upon fracture of the envelope of said bulb together causing said bulbterminals to be moved out of contact with said battery contact springand ejector contact spring.

2. In a flashlight the combination of: a metal shell adapted to `encloseat least one battery; a bulb socket made of an insulating materialrigidly affixed to one end of said shell adjacent to the lens of saidflashlight and adapted to axially movably receive the base of a lightbulb that is seated therein; a battery contact spring mounted on saidsocket that resiliently yields to insertion of said bulb into saidsocket and comprises the electrical connection of one terminal of saidbattery to one terminal of said bulb; a bulb ejector contact springmounted on said socket that resiliently yields to insertion of said bulbinto said socket and adapted to comprise the electrical connection ofthe other terminal of said bulb to a switch means of which said ejectorspring is a part; and a compression spring extending between the lens ofsaid flashlight and the envelope of said bulb to seat said bulb in saidsocket and to hold the terminals of said bulb in contact with saidejector spring and battery contact spring whereby said bulb iselectrically connected to said battery in such a way that when said lensor the envelope of said bulb is broken said ejector spring and batterycontact spring move said bulb away from said contact springs andoutwardly from said socket to break said electrical connections.

3. :In a flashlight for use with a bulb having a smooth cylindrical basethat is outwardly lianged at its junction with the envelope of saidbulb, the combination including: a substantially tubular metal shellthat is adapted to enclose at leastk one battery; a bulb socket made ofan insulating material fastened to the front end of said shell adjacentto the lens of said flashlight, said socket having an axial boretherethrough adapted to have the base of said bulb inserted therein,said bore being spot-faced at its forward end to provide a seat for theflange of said bulb base; a battery contact spring on the inner end ofsaid socket having aresilient finger portion adapted for yieldableengagement with the centrally disposed terminal of said bulb; an ejectorcontact spring on the inner end of said socket having a bifurcated innerend portion adapted to yieldably engage peripheral rear end portions ofthe base of said bulb, said portions constitutingthe other terminal ofsaid bulb; switch means on said shell including said ejector spring thaton closing engage lthe outer end of said ejector spring; and a spring onthe center of the inner face of a lens of said flashlight thatcompressively engages the envelope of said bulb to seat it in saidsocket for electrical connection to batteries in said flashlight throughsaid contact springs so that upon fracture of said lens or bulb envelopethe base of said bulb is thrust outwardly by said ejector spring andbattery contact member whereby to break said electrical corinection.

4. A device as set forth in claim 3 in which the lens is held in one endof a rubber-like outer casing, said lens and casing together providing afluid-sealed housing for said ashlight.

5. In a flashlight for use with a bulb having a smooth cylindrical basethat is outwardly tianged at its junction with the envelope of saidbulb, the combination including: a fluid-sealed housing for saidflashlight comprising a tubular casing of an impervious rubber-likematerial closed at the rear end by an integrally formed wall and a lensset in uid-sealing engagement in'the frontendl of said casing; asubstantially tubular metal shell adapted to be slideably received insaid casing for enclosing at least one battery; a bulb socket made of aninsulating material fastened to the front end of said shell adjacentSaid lens, said socket having an axial bore therethrough adapted to havethe base of said bulb inserted therein, said bore being spot faced atits forward end to provide a seat for the flange of said bulb base; abattery Contact member. fastened in diametrically extending positionacross the rear end of said socket and over said axial j bore andformedl with a central rearwardly extending dimple for electricalcontact with a center terminal of said battery and having a forwardlyand reversely folded resilient finger portion adapted for yieldablecontact with a centrally disposed terminal of said bulb; an ejectorlcontact spring on the inner end of said socket having a bifurcatedinnerl` end portion intercepting said axial bore and adapted toyieldably engage'peripheral rear end portions of said bulb, saidportions constituting the other terminal of said bulb, the outer endportion of said ejector contact spring protruding outwardly through saidmetal shell for switching engagement with a manual switch mounted onsaid shell, said switch being depressible through a side wall portion ofsaid casing to electrically close against the outer end of said ejectorspring to complete a circuit comprising said battery, said shell, saidbattery contact member, Said ejector spring, and said bulb; and a springon the. center of the inner face of said lens that compressively engagesthe envelope of said bulb to seat said bulb in said socket forelectrical connection to said batteries through said contact springs sothat upon fracture of said lens or bulb envelope, the base of said bulbis thrust outwardly of said socket by said ejector spring and batterycontact member and away from said ejector spring andbattery contactmember whereby to break from said ejector spring and battery contactmember whereby to break said electrical connection to avoid ignition ofmaterials entering said flash? interconnect. them; and a resilientAswitch contact! means mounted on said socket and operatively associatedwith a switch means and adapted to electrically interconnect said switchmeans and another terminal of said bulb, both said contact means beingadapted to oppose the force of said yieldable means to thrust said bulbont of said socket only upon fracture of said bulb or said lens.

7. In a ashlight including a lens, a switch means, a socket of aninsulating material ada ted toaxially movably receive the base of a bulbseated in said socket, and a means between said bulb and lens yieldablyurging said bulb into a seated position in said socket, the improvementcomprising the combination of: a unitary means mounted on said socketthat is made of a resiliently deformable materialr and is yieldablyengageable by one terminal of said bulb and is adapted to comprise thesole electrical connection between said one bulb terminal and a terminalof a battery` receivable in said flashlight; and a unitary means mountedon said socket that is made of a resiliently deformable material and isyieldably engageable by the other terminal of said bulb and is adaptedto comprise the sole electrical connection between said other bulbterminal and a switch means of said ashlight, both said unitary meansbeing adapted to oppose said yieldable means to thrust said bulb out.ofv said socket only upon fracture of said bulb or of saidlens. i

S. In a ashlight includingv a lens, a switch means, a socket adapted toaxially movably receive the base of a bulb seated in. said socket,l anda means between said bulb and said lens yieldably urging said bulb intoa seated position in` saidy socket, thev improvement comprising thecombination of: a spring member of a conductingrnatetial mounted on saidsocket and having a portion depressible by one. terminal of said bulband another portion in contact withone terminalof a battery receivablein said flashlight to electrically connect said battery and said onebulb terminal; a second spring member of a conducting material mountedon said socket and insulated fromsaid first member and having a portiondepressible by the other terminal of said bulb, said second member beingadapted to electrically connect said other bulb terminal to a switchVmeans of which said second member is a part, both saidA members beingadapted to oppose said yieldable means to thrust said bulb out of saidsocket only upon fracture of saidr bulb or said lens..

9. In a. flashlight for use with aibulb having a smooth,

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cylindrical baseand including a lens, a switchineans, and a springmeanson said lens adapted to yieldably urge said bulb into a seatedposition in a socket of said flashlight, the improvement comprising thecombination of: a bulb socket made of an insulating materialV that hasan axial bore therethrough adapted to axially, slideably receive and toseat the base of said bulb; a battery contact member fastened indiametrically extending position on said socket over the rear end ofsaid axial bore and having a portion adapted for electrical contact Withone terminal of a battery in said ashlight and having a forwardly andreversely folded resilient nger portion adapted for yieldable contactwith a centrally disposed terminal of said bulb, said battery contactmember comprising the sole electrical connection between said centralterminal of said bulband said battery; an ejector contact springfastened to said socket formed with a bifurcated inner end portioninterceptingsaid axial bore of said socket that is adapted to yieldablyengage peripheral rear end portions of said bulb, which portionsconstitute the other terminal of said bulb, the outer end of saidejector contact spring comprising a portion of a switch means for saidflashlight an-:l said ejector contact spring comprising the soleelectrical connection between said other terminal of said bulb and saidswitch means, both said springs beingfadapted to oppose said springmeans for yieldably urging said bulb into seated position and adapted toboth thrust said bulb outr of said bore of said socket only uponfracture of' said bulb or said lens. f l

References Cited inthe file of this patent Y UNITED STATES PATENTS988,321

OTHER REFERENCES Eveready l-"lashlightsY and Fresh Batteries DescriptiveCatalog No, A1352, October 22, 1937, National Carbon Co. Inc., pagesrlOand 1'1.

Bureau ofV Mines-Bulletin 441-pp. 26-29 and Figures 16 and 17 cited.

